CN110062377B - Power division factor and beam forming combined optimization method in safe energy-carrying communication - Google Patents

Power division factor and beam forming combined optimization method in safe energy-carrying communication Download PDF

Info

Publication number
CN110062377B
CN110062377B CN201910221146.1A CN201910221146A CN110062377B CN 110062377 B CN110062377 B CN 110062377B CN 201910221146 A CN201910221146 A CN 201910221146A CN 110062377 B CN110062377 B CN 110062377B
Authority
CN
China
Prior art keywords
node
relay node
power division
beam forming
division factor
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN201910221146.1A
Other languages
Chinese (zh)
Other versions
CN110062377A (en
Inventor
许晓荣
胡安迪
姚英彪
刘兆霆
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hangzhou Dianzi University
Original Assignee
Hangzhou Dianzi University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hangzhou Dianzi University filed Critical Hangzhou Dianzi University
Priority to CN201910221146.1A priority Critical patent/CN110062377B/en
Publication of CN110062377A publication Critical patent/CN110062377A/en
Application granted granted Critical
Publication of CN110062377B publication Critical patent/CN110062377B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B7/00—Radio transmission systems, i.e. using radiation field
    • H04B7/02—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas
    • H04B7/04—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
    • H04B7/06—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
    • H04B7/0613—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission
    • H04B7/0615—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal
    • H04B7/0617—Diversity systems; Multi-antenna system, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station using simultaneous transmission of weighted versions of same signal for beam forming
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W12/00—Security arrangements; Authentication; Protecting privacy or anonymity
    • H04W12/009—Security arrangements; Authentication; Protecting privacy or anonymity specially adapted for networks, e.g. wireless sensor networks, ad-hoc networks, RFID networks or cloud networks
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/02—Communication route or path selection, e.g. power-based or shortest path routing
    • H04W40/04—Communication route or path selection, e.g. power-based or shortest path routing based on wireless node resources
    • H04W40/08—Communication route or path selection, e.g. power-based or shortest path routing based on wireless node resources based on transmission power
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/02—Communication route or path selection, e.g. power-based or shortest path routing
    • H04W40/12—Communication route or path selection, e.g. power-based or shortest path routing based on transmission quality or channel quality
    • H04W40/16—Communication route or path selection, e.g. power-based or shortest path routing based on transmission quality or channel quality based on interference
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W40/00—Communication routing or communication path finding
    • H04W40/02—Communication route or path selection, e.g. power-based or shortest path routing
    • H04W40/22—Communication route or path selection, e.g. power-based or shortest path routing using selective relaying for reaching a BTS [Base Transceiver Station] or an access point

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Computer Security & Cryptography (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

The invention discloses a power division factor and beam forming combined optimization method in safe energy-carrying communication. The invention comprises the following steps: step 1, power division factor and beam forming joint optimization method scene assumption and modeling in safe energy-carrying communication; step 2, selecting a strategy of an optimal relay node in a power division factor and beam forming combined optimization method in safe energy-carrying communication; step 3, designing a receiving beam forming vector of an optimal relay node in a power division factor and beam forming combined optimization method in safe energy-carrying communication; and 4, jointly optimizing the power division factor and the transmitting beam forming vector of the optimal relay node in the safe energy-carrying communication power division factor and beam forming joint optimization method. The method ensures the requirement of safe communication performance in the SWIPT communication network.

Description

Power division factor and beam forming combined optimization method in safe energy-carrying communication
Technical Field
The invention belongs to the technical field of information and communication engineering, and provides a joint optimization method for a plurality of relay node optimal power division factors and beam forming vectors with power division receivers in a safe wireless energy-carrying communication network.
Background
With the popularization of smart phones and the abundance of mobile internet application contents, people's demand for mobile communication services is far beyond the basic functions of voice, short messages and the like. In addition, the rapid rise of the internet of things industry further expands the service range of mobile communication from the current person-to-person communication to person-to-object and object-to-object communication, and then the mass devices in the network are connected at the same time. Mobile communication data traffic has been shown to grow exponentially in recent years and is expected to continue to grow at a high rate for a longer period of time in the future. However, this explosive growth also leads to a dramatic increase in energy consumption across the transmit and receive ends. The increasing energy consumption places a heavy burden on communication devices that use battery power (e.g., communication nodes in the internet of things or wireless sensor networks). In order to extend the operating life of the entire communication network, the communication nodes need to be frequently replaced with batteries or charged, which necessarily results in an increase in maintenance costs. In particular, for some communication nodes deployed in special application environments (for example, measurement and control nodes deployed in harsh environments such as high altitude, low pressure, severe cold, and the like), maintenance of equipment is more difficult. Although manufacturers extend the working time of the devices by reducing the power consumption of the chips, optimizing the operating system, and the like when developing the smart devices, the manufacturers still cannot meet the increasing working and living requirements of people in practical application. Therefore, better methods are always sought to solve the problem of power consumption of the terminal device.
In recent years, Energy Harvesting (EH) technology has become one of the research hotspots in the communications industry. The energy collecting device obtains energy from the surrounding environment in the non-communication idle time slot, and the common energy sources comprise solar energy, wind energy, geothermal energy, vibration energy and the like. Although natural energy is taken as the source for collecting energy, the energy consumption of the network can be further saved, the natural energy is greatly influenced by external factors such as weather, the collection efficiency is very limited, and the stability of the communication network can be influenced. On the basis, the students find that Radio Frequency (RF) signals can carry energy while transmitting information, and are more controllable and relatively longer in propagation distance compared with natural energy such as solar energy. Therefore, it is an effective way to obtain energy from RF signals, and Wireless energy Transfer (SWIPT) technology has been developed. In a communication system equipped with the SWIPT technology, communication equipment can utilize radio frequency signals to complete energy collection, and various interferences in a network can be converted into energy benefits of the equipment, so that the technology can solve the problem that node energy in the network is limited, can also improve the utilization efficiency of energy in the environment, and is about to bring a revolution to new-generation wireless communication.
No matter how the network scale develops and the network form changes, guaranteeing the information safety is always one of the subjects of invariance in the communication system. The SWIPT technology realizes the parallel transmission of energy and information by using an RF signal, but the characteristics of openness and broadcast of a wireless signal cause the wireless signal to be easily subjected to illegal eavesdropping by an eavesdropper. Traditional encryption mechanisms based on computational load solve the problem of secure transmission of wireless information from upper layers such as the application layer of a protocol stack, which often assumes that the computational power of an eavesdropper is limited and that the system has perfect secure key management and distribution mechanisms. However, the security of the conventional encryption method faces many problems due to the increase of the computing power of the eavesdropper, the mobility of the wireless communication node and the limitation of available resources. In recent years, it has become a research hotspot to research security of wireless communication from the perspective of a physical layer. The wireless Physical Layer Security (PLS) technology based on the information theory ensures the secure transmission of wireless information by using the randomness, the difference, the reciprocity and other Physical characteristics of a main channel and an eavesdropping channel, has attracted wide attention in the academic and industrial fields at home and abroad to solve the Security problem in the SWIPT system by using the idea of Physical Layer Security, can avoid a complex upper Layer encryption mode, and simultaneously meets the practical requirements of energy wireless transmission and reliable and secure information transmission, thereby having very wide application prospect. The main technical indexes for evaluating the safety performance of the SWIPT communication system are as follows: safe communication rate, information interception probability, safe energy efficiency and the like.
Disclosure of Invention
The invention aims to provide a joint optimization method of an optimal power division factor and a beam forming vector of a relay node of a safe SWIPT communication network aiming at the safe communication between a transmitting node and a target node of the SWIPT communication network under the condition that a plurality of relay nodes provided with power division receivers exist, and a specific communication flow is provided. The method relates to a selection strategy of an optimal relay node in a safe wireless energy-carrying communication network, a receiving beam forming vector design of the optimal relay node, and joint optimization of a power division factor and a sending beam forming vector of the optimal relay node, and mainly relates to a joint optimization method of the optimal power division factor and the beam forming of the relay node for guaranteeing a safe communication rate in the safe wireless energy-carrying communication network.
The technical scheme of the problem solved by the invention comprises the following steps:
step 1, power division factor and beam forming joint optimization method scene assumption and modeling in safe energy-carrying communication:
without loss of generality, before describing the design strategy in detail, the following assumptions are made:
(1) the whole communication time slot is assumed to be normalized to 1 and equally divided into two communication stages;
(2) legal nodes can obtain state information of all channels, and all channels in the system are subject to Rayleigh flat fading;
(3) in the SWIPT network, a sending node and a destination node cannot directly communicate and need to be forwarded through a relay node.
In the first stage, the SWIPT network sends node (Source, S) with power PSBroadcasting a signal x of unity powerS. At the same time, Destination node (D) of SWIPT network uses power PDBroadcasting interference signal x of unit powerD。
M relay nodes Ri(i-1, 2, …, M) can receive the signal xSAnd interference signal xDEach relay node is equipped with N antennas. The SWIPT network selects the optimal relay node R from the M relay nodes by using the optimal relay node selection strategybThe best relay node RbThe received signals are:
Figure BDA0002003652760000031
wherein h isbAnd gbRespectively a sending node S to an optimal relay node RbAnd destination node D to optimal relay node RbNx1 channel vector of the link; n isbIs the best relay node RbAt an Nx 1 noise vector with a noise power of
Figure BDA0002003652760000032
Optimal relay node RbA power-split receiver is used to split the received signal into two parts with a power-split factor ρ (0 ≦ ρ ≦ 1). One part is used for information decoding and the other part is used for energy collection.
Optimal relay node RbThe partial signals used for energy harvesting are:
Figure BDA0002003652760000041
optimal relay node RbThe energy collected here is:
Figure BDA0002003652760000042
wherein eta represents energy conversion efficiency and satisfies 0 ≦ eta ≦ 1.
Optimal relay node RbThe partial signals used for information decoding are:
Figure BDA0002003652760000043
wherein n iscFor noise generated when the RF signal is converted into the baseband signal, the mean value is 0 and the variance is
Figure BDA0002003652760000044
To avoid interference signals sent by the destination node D to the optimal relay node RbApplying a receive beamforming vector w to a partial signal for information decodingR。
Optimal relay node RbThe estimated signal at (a) is expressed as:
Figure BDA0002003652760000045
wherein
Figure BDA0002003652760000046
Representing receive beamforming vectors wRThe conjugate transpose of (c).
Optimal relay node RbThe signal to interference plus noise ratio is expressed as:
Figure BDA0002003652760000047
in this stage, an eavesdropping node (Eavesdropper, E) can perform illegal eavesdropping, and the signal and the received signal-to-interference-and-noise ratio acquired by the eavesdropping node E are respectively:
Figure BDA0002003652760000048
Figure BDA0002003652760000049
wherein h isSEAnd hDEChannel coefficients for the S to E and D to E links, respectively; n isE1Is a mean of 0 and a variance of
Figure BDA0002003652760000051
White additive gaussian noise.
Second stage, the best relay node R selectedbThe energy collected in the first stage is used to decode the forward (DF) protocol to help forward data for the SWIPT network. At the best relay node RbHere, the transmission signal is represented as:
Figure BDA0002003652760000052
wherein wDIs a transmit beamforming vector for destination node D of the SWIPT network.
At this stage, the received signal at the destination node D is represented as.
Figure BDA0002003652760000053
Wherein the content of the first and second substances,
Figure BDA0002003652760000054
as the best relay node RbNx 1 channel vector q for link to destination node DbThe conjugate transpose of (1); n isDThe mean value at the destination node D is 0 and the variance is
Figure BDA0002003652760000055
White additive gaussian noise.
At this stage, the signal-to-noise ratio at the destination node D is expressed as:
Figure BDA0002003652760000056
wherein, PrRepresenting the power to be distributed, expressed as
Figure BDA0002003652760000057
During this phase, the received signal at Eve is represented as:
Figure BDA0002003652760000058
wherein the content of the first and second substances,
Figure BDA0002003652760000059
as the best relay node RbNx 1 channel vector z to eavesdropping node E linkbThe conjugate transpose of (1); n isE2Is a mean of 0 and a variance of
Figure BDA00020036527600000510
White additive gaussian noise.
At this stage, the signal-to-noise ratio at E is expressed as:
Figure BDA00020036527600000511
the eavesdropping node combines the signals received in the two stages, and the communication rate is represented as:
Figure BDA00020036527600000512
due to the best relay node RbAnd forwarding the data of the sending node S by using the DF protocol, wherein the communication rate of the SWIPT network is expressed as follows:
Figure BDA0002003652760000061
wherein, min [ log ]2(1+γS1),log2(1+γS2)]Is expressed log2(1+γS1)、log2(1+γS2) The smaller of the two. The secure communication rate is defined as the difference between the communication rate of the SWIPT network and the communication rate of the eavesdropping node, and the expression is as follows:
R＝[RS-RE]+ (16)
wherein R ═ RS-RE]+Is represented by RS-REThe negative part is set to 0.
Step 2, selecting a strategy of an optimal relay node in a power division factor and beam forming combined optimization method in safe energy-carrying communication:
firstly, channel state information h between a SWIPT network sending node and each relay node in the network is obtainedi(i ═ 1,2, …, M), then the best relay node is chosen according to the following criteria:
Figure BDA0002003652760000062
step 3, designing a receiving beam forming vector of an optimal relay node in a power division factor and beam forming joint optimization method in safe energy-carrying communication:
in order to avoid the influence of interference signals sent by a destination node of the SWIPT network on information decoding of the optimal relay node, w is enabledRSatisfies the following conditions:
Figure BDA0002003652760000063
final design wRThe following were used:
Figure BDA0002003652760000064
wherein the content of the first and second substances,
Figure BDA0002003652760000065
INrepresenting an identity matrix of size N.
Step 4, jointly optimizing the power division factor and the transmission beam forming vector of the optimal relay node in the safe energy-carrying communication power division factor and beam forming joint optimization method:
in order to weaken the interception of the interception node to the optimal relay node, w is designedDThe following were used:
Figure BDA0002003652760000071
wherein the content of the first and second substances,
Figure BDA0002003652760000072
INrepresenting an identity matrix of size N.
Since the optimal relay node uses the DF protocol to transmit the data signal of the node, when gamma isS1＝γS2When R isSReaches a maximum value so that R takes a maximum value. And because of gammaS1Will increase with increasing ρ, γS2Decreases as ρ increases. So will storeLet equation γ be at one ρS1＝γS2This holds true, and ρ at this time is the optimal power division factor.
The method for optimizing the power division factor of the optimal relay node specifically comprises the following steps:
(1) initialization: rhomin＝0，ρ max1, tolerance δ 0.05
(2) When rhomax-ρminWhen δ, the following loop is performed:
taking rho ═ rhomax+ρmin)/2；
② calculating gammaS1And gammaS2And calculating gammaS2-γS1；
③ when gammaS2-γS1When > 0, update rhominρ; otherwise, update rhomax＝ρ。
(3) And the loop is ended, and the rho at the moment is the optimal power division factor.
The invention has the following beneficial effects:
the invention takes wireless energy-carrying communication (SWIPT) as a research background, introduces a plurality of SWIPT relay nodes provided with power division receivers, and researches a combined optimization method of power division factors and beam forming in a safe SWIPT communication network. The method establishes an optimization model by taking the maximum safe communication rate as an optimization target under the condition that a plurality of relay nodes provided with power division receivers exist in the SWIPT safe communication network, and enables the system performance to meet the required requirements through the selection of the optimal relay nodes, the design of the receiving beam forming vectors of the optimal relay nodes, and the joint optimization of the power division factors and the sending beam forming vectors of the optimal relay nodes. The invention analyzes the influence of the power division factor of the optimal relay node, the sending power of the sending node, the interference power of the target node and the relay number on the safe communication rate. Research shows that with the increase of the optimal relay node power division factor, the safe communication speed is increased firstly and then decreased, the optimal relay can obtain the maximum system safe speed by selecting the optimal power division factor, and the effectiveness of the optimal relay node power division factor optimization method is verified. With the increase of the node transmission power, the safe communication speed tends to be gentle after being increased. With the increase of the interference power of the destination node, the safe communication speed is increased slowly and then rapidly. With the increase of the number of relays, the safe communication speed tends to be gentle after being increased. Under the condition of a plurality of SWIPT relay nodes provided with power splitting receivers, the method ensures the requirement of safe communication performance in the SWIPT communication network.
Drawings
Fig. 1 is a diagram of a first-stage communication model of a power division factor and beam forming joint optimization method in secure energy-carrying communication.
Fig. 2 is a diagram of a second-stage communication model of a power division factor and beamforming joint optimization method in secure energy-carrying communication.
Fig. 3 illustrates the impact of the power splitting factor of the best relay node on the safe communication rate.
Fig. 4 is a graph of the effect of transmit power of a transmitting node on a safe communication rate.
Fig. 5 illustrates the effect of interference power of the destination node on the safe communication rate.
Fig. 6 is a graph of the impact of the number of relays on the rate of secure communication.
Detailed Description
Fig. 1 is a diagram of a first-stage communication model of a power division factor and beam forming joint optimization method in secure energy-carrying communication. At this stage, the transmitting node broadcasts a data signal to a plurality of relay nodes equipped with power-split receivers, while the destination node broadcasts an interfering signal to interfere with the eavesdropping node. The safe SWIPT communication network selects the optimal relay node according to the optimal relay node selection strategy, and the optimal relay node performs information decoding and energy collection on the received signal at the same time.
Fig. 2 is a diagram of a second-stage communication model of a power division factor and beamforming joint optimization method in secure energy-carrying communication. At this stage, the best relay node forwards the data.
Figure 3 shows the effect of the power split factor of the best relay node on the safe communication rate. As can be seen from the figure, as the power division factor of the optimal relay node increases, the secure communication rate increases first and then decreases, which indicates that the optimal relay can obtain the maximum system secure rate by selecting the optimal power division factor, and verifies the effectiveness of the optimization method of the power division factor of the optimal relay node.
Fig. 4 shows the effect of the transmit power of the transmitting node in the secure SWIPT communication network on the secure communication rate for different numbers of relay nodes. The interference power of a given target node is 20 dBm; the noise is assumed to be white gaussian noise, and the noise power is 1 mW. As can be seen from the figure, as the transmission power of the transmitting node increases, the safe communication rate increases continuously and then becomes flat. The increase in the number of relay nodes can achieve a higher secure communication rate with the same transmission power of the transmission node.
Fig. 5 shows the influence of the interference power of the destination node in the secure SWIPT communication network on the secure communication rate under different numbers of relay nodes. The transmitting power of a given transmitting node is 30 dBm; the noise is assumed to be white gaussian noise, and the noise power is 1 mW. As can be seen from the figure, as the interference power of the destination node increases, the safe communication rate increases slowly and then increases rapidly. Under the condition of having the same target node interference power, the number of the relay nodes is increased, so that a higher safe communication speed can be obtained.
Fig. 6 shows the effect of the number of relays of the secure SWIPT communication network on the secure communication rate. The sending power of a given sending node is 30dBm, and the interference power of a target node is 20 dBm; the noise is assumed to be white gaussian noise, and the noise power is 1 mW. As can be seen from the graph, as the number of relays increases, the safe communication speed increases first and then becomes gentle.
It should be understood by those skilled in the art that the above embodiments are only used for illustrating the present invention and are not to be taken as limiting the present invention, and the changes and modifications of the above embodiments are within the scope of the present invention.

Claims (2)

1. The power division factor and beam forming joint optimization method in the safe energy-carrying communication is characterized by comprising the following steps:
step 1, power division factor and beam forming joint optimization method scene assumption and modeling in safe energy-carrying communication;
step 2, selecting a strategy of an optimal relay node in a power division factor and beam forming combined optimization method in safe energy-carrying communication;
step 3, designing a receiving beam forming vector of an optimal relay node in a power division factor and beam forming combined optimization method in safe energy-carrying communication;
step 4, jointly optimizing the power division factor and the transmission beam forming vector of the optimal relay node in the safe energy-carrying communication power division factor and beam forming joint optimization method;
the method for jointly optimizing the power division factor and the beam forming in the safe energy-carrying communication in the scene hypothesis and the modeling specifically comprises the following steps:
the following definitions are made:
(1) the whole communication time slot is normalized to 1 and equally divided into two communication stages;
(2) legal nodes obtain state information of all channels, and all channels in the system are subject to Rayleigh flat fading;
(3) in a wireless energy-carrying communication SWIPT network, a sending node S and a destination node D do not directly communicate and are forwarded through a relay node;
in the first phase, the SWIPT network sends the node S with power PSBroadcasting a signal x of unity powerS(ii) a Meanwhile, destination node D of SWIPT network uses power PDBroadcasting interference signal x of unit powerD；
M relay nodes RiReceived signal xSAnd interference signal xDWherein i ═ 1,2, …, M; each relay node is provided with N antennas; the SWIPT network selects the optimal relay node R from the M relay nodes by using the optimal relay node selection strategybThe best relay node RbThe received signals are:
Figure FDA0003512668660000011
wherein h isbAnd gbRespectively a sending node S to an optimal relay node RbAnd destination node D to optimal relay node RbNx1 channel vector of the link; n isbIs the best relay node RbAt an Nx 1 noise vector with a noise power of
Figure FDA0003512668660000021
Optimal relay node RbDividing the received signal into two parts with a power division factor ρ using a power division receiver; one part is used for information decoding, and the other part is used for energy collection; wherein rho is more than 0 and less than 1;
optimal relay node RbThe partial signals used for energy harvesting are:
Figure FDA0003512668660000022
optimal relay node RbThe energy collected here is:
Figure FDA00035126686600000210
wherein eta represents energy conversion efficiency and satisfies 0 < eta < 1;
optimal relay node RbThe partial signals used for information decoding are:
Figure FDA0003512668660000023
wherein n iscFor noise generated when the RF signal is converted into the baseband signal, the mean value is 0 and the variance is
Figure FDA0003512668660000024
To avoid interference signals transmitted by the destination node DNumber pair optimal relay node RbApplying a receive beamforming vector w to a partial signal for information decodingR；
Optimal relay node RbThe estimated signal at (a) is expressed as:
Figure FDA0003512668660000025
wherein
Figure FDA0003512668660000026
Representing receive beamforming vectors wRThe conjugate transpose of (1);
optimal relay node RbThe signal to interference plus noise ratio is expressed as:
Figure FDA0003512668660000027
in the first stage, the eavesdropping node E performs illegal eavesdropping, and the signal and received signal-to-interference-and-noise ratio obtained by the eavesdropping node E are respectively:
Figure FDA0003512668660000028
Figure FDA0003512668660000029
wherein h isSEAnd hDEChannel coefficients for the S to E and D to E links, respectively; n isE1Is a mean of 0 and a variance of
Figure FDA0003512668660000031
Additive white gaussian noise of (1);
second stage, the best relay node R selectedbUsing the energy collected in the first stage to decode the forwarding protocol to assist in forwarding a SWIPT networkThe data of (a); at the best relay node RbHere, the transmission signal is represented as:
Figure FDA0003512668660000032
wherein wDIs a transmit beamforming vector for a destination node D of the SWIPT network;
the received signal at the destination node D in the second stage is represented as:
Figure FDA0003512668660000033
wherein the content of the first and second substances,
Figure FDA0003512668660000034
as the best relay node RbNx 1 channel vector q for link to destination node DbThe conjugate transpose of (1); n isDThe mean value at the destination node D is 0 and the variance is
Figure FDA0003512668660000035
Additive white gaussian noise of (1);
the signal-to-noise ratio at the destination node D in the second stage is expressed as:
Figure FDA0003512668660000036
wherein, PrRepresenting the power to be distributed, expressed as
Figure FDA00035126686600000312
The received signal at the eavesdropping node E in the second phase is represented as:
Figure FDA0003512668660000037
wherein the content of the first and second substances,
Figure FDA0003512668660000038
as the best relay node RbNx 1 channel vector z to eavesdropping node E linkbThe conjugate transpose of (1); n isE2Is a mean of 0 and a variance of
Figure FDA0003512668660000039
Additive white gaussian noise of (1);
the signal-to-noise ratio at E in the second stage is expressed as:
Figure FDA00035126686600000310
the eavesdropping node combines the signals received in the two stages, and the communication rate is represented as:
Figure FDA00035126686600000311
due to the best relay node RbAnd forwarding the data of the sending node S by using the DF protocol, wherein the communication rate of the SWIPT network is expressed as follows:
Figure FDA0003512668660000041
wherein, min [ log ]2(1+γS1),log2(1+γS2)]Is expressed log2(1+γS1)、log2(1+γS2) The smaller of the two; the secure communication rate is defined as the difference between the communication rate of the SWIPT network and the communication rate of the eavesdropping node E, and the expression is as follows:
R＝[RS-RE]+ (16)
wherein R ═ RS-RE]+Is represented by RS-RESetting the negative part to 0;
and 3, designing a receiving beam forming vector of the optimal relay node in the safe energy-carrying communication power division factor and beam forming joint optimization method specifically as follows:
in order to avoid the influence of interference signals sent by the destination node D of the SWIPT network on the information decoding of the optimal relay node, w is enabledRSatisfies the following conditions:
Figure FDA0003512668660000042
final design wRThe following were used:
Figure FDA0003512668660000043
wherein the content of the first and second substances,
Figure FDA0003512668660000044
INrepresenting an identity matrix of size N;
step 4, in the method for jointly optimizing power division factors and beam forming in secure energy-carrying communication, the power division factors and the transmit beam forming vectors of the optimal relay node are jointly optimized, specifically as follows:
in order to weaken the interception of the interception node E to the optimal relay node, design wDThe following were used:
Figure FDA0003512668660000045
wherein the content of the first and second substances,
Figure FDA0003512668660000046
INrepresenting an identity matrix of size N;
since the optimal relay node forwards the data signal of the transmitting node using the DF protocol, when gamma isS1＝γS2When R isSReaches a maximum value such that R takes a maximum value; and because of gammaS1Increases with increasing ρ, γS2Decreases with increasing ρ; so that there is one ρ making the equation γS1＝γS2And then rho is the optimal power division factor;
the method for optimizing the power division factor of the optimal relay node specifically comprises the following steps:
(1) initialization: rhomin＝0，ρmax1, tolerance δ 0.05
(2) When rhomax-ρminWhen δ, the following loop is performed:
taking rho ═ rhomax+ρmin)/2；
② calculating gammaS1And gammaS2And calculating gammaS2-γS1；
③ when gammaS2-γS1When > 0, update rhominρ; otherwise, update rhomax＝ρ；
(3) And the loop is ended, and the rho at the moment is the optimal power division factor.
2. The method as claimed in claim 1, wherein the selection strategy of the best relay node in the method for jointly optimizing power division factor and beamforming in the secure energy-carrying communication in step 2 is as follows:
firstly, channel state information h between a SWIPT network sending node and each relay node in the network is obtainedi(ii) a Then, the best relay node is selected according to the following criteria:
Figure FDA0003512668660000051
wherein i is 1,2, …, M.
CN201910221146.1A 2019-03-22 2019-03-22 Power division factor and beam forming combined optimization method in safe energy-carrying communication Active CN110062377B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201910221146.1A CN110062377B (en) 2019-03-22 2019-03-22 Power division factor and beam forming combined optimization method in safe energy-carrying communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201910221146.1A CN110062377B (en) 2019-03-22 2019-03-22 Power division factor and beam forming combined optimization method in safe energy-carrying communication

Publications (2)

Publication Number Publication Date
CN110062377A CN110062377A (en) 2019-07-26
CN110062377B true CN110062377B (en) 2022-04-08

Family

ID=67317198

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201910221146.1A Active CN110062377B (en) 2019-03-22 2019-03-22 Power division factor and beam forming combined optimization method in safe energy-carrying communication

Country Status (1)

Country Link
CN (1) CN110062377B (en)

Families Citing this family (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110446186B (en) * 2019-08-07 2022-04-29 长安大学 Physical layer secure communication method based on SWIPT in Internet of vehicles
CN111884688B (en) * 2020-06-23 2021-09-21 杭州电子科技大学 OPS structure-based R-E domain optimization method for multi-node multi-antenna SWIPT network
CN112543472B (en) * 2020-11-20 2022-06-21 杭州电子科技大学 Multi-relay time slot and power joint optimization method based on DTPS (delay tolerant packet switching) protocol in cognitive SWIPT (switched Power packet exchange protocol)
CN112637925B (en) * 2020-11-28 2022-06-03 重庆财经学院 Safe relay selection method based on random forest non-uniform quantitative feature extraction
CN113518359B (en) * 2021-04-29 2023-02-07 东北大学 Optimization method for combining multi-relay selection and power division factor based on speed
CN114884550B (en) * 2022-04-06 2023-07-25 南京邮电大学 Relay cooperative transmission method for bidirectional transmission FD multi-relay cooperative SWIPT network

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104702372A (en) * 2015-02-12 2015-06-10 郑州大学 MU-DAS simultaneous wireless information and power transfer optimal robustness construction method
CN105450327A (en) * 2015-12-07 2016-03-30 桂林电子科技大学 Physical-layer-secure wireless energy-carrying communication method
EP3447885A1 (en) * 2017-08-25 2019-02-27 Vestel Elektronik Sanayi ve Ticaret A.S. A system for harvesting energy and a method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104702372A (en) * 2015-02-12 2015-06-10 郑州大学 MU-DAS simultaneous wireless information and power transfer optimal robustness construction method
CN105450327A (en) * 2015-12-07 2016-03-30 桂林电子科技大学 Physical-layer-secure wireless energy-carrying communication method
EP3447885A1 (en) * 2017-08-25 2019-02-27 Vestel Elektronik Sanayi ve Ticaret A.S. A system for harvesting energy and a method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
多天线FD-SWIPT中继信道下功率***和波束成形的联合优化;扶渝茜等;《重庆邮电大学学报(自然科学版)》;20171015;第29卷(第05期);第649-656页 *

Also Published As

Publication number Publication date
CN110062377A (en) 2019-07-26

Similar Documents

Publication Publication Date Title
CN110062377B (en) Power division factor and beam forming combined optimization method in safe energy-carrying communication
CN107172705B (en) Beam optimization method and system of wireless energy-carrying heterogeneous network
CN107171764B (en) Secure transmission method and system of wireless energy-carrying heterogeneous network
CN108601042B (en) Relay auxiliary information and energy transmission method based on time slot switching
Zhuang et al. Exploiting intelligent reflecting surface for energy efficiency in ambient backscatter communication-enabled NOMA networks
CN108521666B (en) Multi-relay system dynamic power distribution method based on nonlinear energy acquisition model
CN109525984B (en) Method for improving safety rate of untrusted relay energy-carrying communication system
CN101557630A (en) Method for selecting cooperative nodes in wireless communication network
CN105071840A (en) united implementing method for node transmitting power and relay node position disposition of AF bidirectional relay communication system
CN109787828B (en) Cognitive SWIPT optimal node selection and beam forming combined design method
CN106549698B (en) The maximization minimum user rate method of bidirectional relay system based on wireless energy transfer
CN110971290B (en) Unmanned aerial vehicle relay cooperative communication system information transmission method with optimal energy efficiency
CN106535202A (en) Hybrid half duplex/full duplex transmission method of relay auxiliary non-authorization user
CN111884688B (en) OPS structure-based R-E domain optimization method for multi-node multi-antenna SWIPT network
CN106953819B (en) Physical layer secret communication method based on multi-radio cooperation precoding
Peng et al. Joint resource optimization for DF relaying SWIPT based cognitive sensor networks
Mao et al. Joint distributed beamforming and backscattering for UAV-assisted WPSNs
Shengnan et al. Physical layer security communication of cognitive UAV mobile relay network
CN110518954B (en) Short wave/ultra-short wave radio station long-distance relay communication system and method
CN112261615B (en) Energy efficiency degradation method based on average field unmanned aerial vehicle auxiliary multi-band dense network
CN104837194A (en) Bidirectional relay system power distribution method based on AF (Amplify-and-Forward) mechanism
CN104780601A (en) Iteration dynamic power separation method in multiple relay channel energy synchronous transmission networks
CN113452470B (en) Signal power optimization method of wireless energy supply communication network
CN115426647B (en) Intelligent super-surface-based secure communication method and system
Tin et al. Hybrid TSR-PSR in nonlinear EH half duplex network: system performance analysis

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant